Pneumatic percussive tool.



C. H'. HAESELER. PNEUMATIC PERCUSSIVE TOOL. APPLICATION FILED MAY l2. 1916.

1240,708. latmmadsept.v 18, 1917.

. 3 SHEETS- SHEET 2.

v llllHl llllllll WITNESSES www @MAZ/ .mr-.Fr 1

INVENTCR @SHEETS-SHEET 3.

Patented sept. 18,1917.

C H HAESELER 'PNEUMATIC PE'RCUSSIVE TOOL. AjPPucATloN min 14m12.191s.

a sears NEUIWATIC PERCUSSIVE TOOL.

Lemans.

To all whom it mayconcem Be it k-noivn that i, CHARLES H. Hansi-anna,

a citizen ofthe 1United States, residing in the city and coun-ty ofl Philadelphia, State ,of

Pennsylvania, have inventeda new and useful Pneumatic Percnssive rfool, of Whichtlie following is a specification.

The object ot my invention is to provide A a pneumatic percussive tool construction that makes for the greatest utility by a combination that 'produces sustained eiiiciency, simplicity, ease of operation, low cost of upkeep, accessibility for repair and reduced cost ot manufacture.

A further object of myl invention is vto provide inicombination with such a teol a valve arrangement independent ofthe: distri` buton valve to relieve the compression of ai." in the ends of the piston casing by which the speed and `force of blow of the hammering piston may be `varied' to better accomplish desired results according to the different character of Work upon which such tools are usually employed. Y

To the abete;V ends my invention consists of a novel percussire tool wherein is employed a n const ructionand arrangement of a luidld ibution valve preferably carried by th read block andlocated out of alineinentf'with the hammering piston, the valve cage of such fluid distribution valve being constructed in suclrfa manner that it may be assembled to bring its ports and passages into proper alinement with the4 ports and passages with Which-it coperates and 'Whe-rein they Yalve cage may be connected and disconnected as a unit of structure when desired without necessitating the removal of the head block `from the easing. The fluid distrilnition'valve is located so v that its housing vvill least obstruct the proper 4and arrangement of a casing having preferablv: but a single passage therein forthe live Specieaton of Letters Patent.

ployed, and to effect the reciprocations of' motive fluid, said passage extending to the foryvard end of the pistonf chamber to eiiect the return ot the reciprocatory piston.

lt further consists of novel means to re,- .duce the compression at one or 'both ends of the piston chamber. n,

Alt further consists of a `novel construction and arrangement of a fluid distribution valve. l l y lt further consists ofl a novel construction et a casing. Y

It further consists cfa novel construction of a compression valve and novel means tor actuating it lwhereby vit is moved in .opposite directions by live motive Huid.

It further consists of a novelconstruction of a. compression valve and novel means for' actuating it whereby it is moved in one? direction by live motive fluid and in .a reverse i direction by compressed motive fluid.

It further consists of a: novel ,construction-` and arrangement et ports and passages to `etiect the shifting of the main distribution valve and of the compression valves, if emthe hammering piston.'

Other novel features ofconstruction. and advantage will hereinafter more clearly ap-.,` .pear inthe detailed description of the invention and in the appended claims.

For the purpose ot illustrating my invention, I' have shown in xthe .accompanying drawings'those' forms thereoil which are at present preferred by me, since the'same Will give in practice satisfactory and reliable re# sults, although itis to be understood .that the various intrumentalities of which my inven`l tion .consists can be variously arranged and lorganized and that my invention is notllimited except by the scope of the appended claims to the precise arrangement and organization of these -instrumentalities-as herein shown and described. i: y y

Figure l represents a longitudinal Isection of a pneumatic hammer embodying #ny invcntion.-

Fig. 2 represents a longitudinal section of 4the hammer seen in Fig. l but showing the tion.

Fig. 4 represents .a` section on line of rig. 1.

orales.;

Patented Sept. 18, 1917.1

. Application tiled May l2, 1916. Serial No.'97,014. 'Y i I i.

' Fig. 6 repres Fig. 5 represents in section the different parts of the fluiddistributing valve as ready for assemblingQf-.-

. ffnts abside elevation, partly in section, of another embodiment of my invention.

Fig. 7 representsfa'transverse section on line. 7-7 of Fig. 6.v if. A

Fig. 8 represents aji'longitudinal section ,of

the hammervwith the 'fluid distribution valve y and the piston in a vdifferent position from transverse section on 1 designates a pneumatic hammer eml` bodying my invention, said hammer comprising va casing 2, which at its rear end is` tapered or converges rearwardly, as at 3,

in order to receive the sleeve or head block 4 connected as shown with a handle- 5, which4 latter is provided with a grasping portion 6. The casing 2is provided with a groove 7 which is adapted to register withv a cornut,` whereby when formed responding groove or recess 8 in the handle sleeve 4, so that when such parts are; in register an apertureis formed to receive the fastening device V9, consisting of a bolt and tightened, he split sleeve 4 will be securely locked with respect to the casing 2, it being noted that the handle sleeve is split, as indicated atl 10.v The handle 6 is `provided with an inlet passage 11 for the motive fluid, the admission of which from the motive fluid supply to said passage is controlled by means'of'a manuallyactuated valve 12 of any desired or conventional type. The sleeve 'of the handle 5 is provided with a boss 13 having a valve cage pocket v14 formed thereinand communicating with the 'passage 11.

15v designates distribution'valve, which is formed of two telescopic sections 16 and 17, respectively.

.The cage section v16 is provided with an* annular groove 18 and the sides and rear face end of the as at 19, in orderto form passages through which the motive Huid passes from the passage 11 into the chamber 20 formed by the annular groove 18. They-cage section 17 is lwith an annular flange. 21 intermediate its ends and with a tubular extension 22, which is adapted to pass into the aperture..23 ofthe cage sectionzl. The opposite end of the cage sectionii is provided with a Vlug 24, the innerl periphery of which is internally threaded. as at 25. yreceive an extracting device, as will behere- 65. nafter pointed ,gint

the fastening device isl the valvecage of the fluid cage-'section 16 are grooved and can only be removed b v first removin in order to Y The cage sections are secured in assembled position by means of a locking and register- 1 ing device 26, the outer end of which extends beyond the periphery of thecage sections 16 and 17, so that it will extend into the longitudinal key way 27 and be guided by the walls thereof during the insertion'andV re moval of the valve cage into or fronrthe pocket 14.Y The valve. cage pocket 14 at its forward end is threaded to receive a recessed cap 28 which contains a spring29, which latter is also adapted to encirclethe lug 24 when the parts are in assembled posi-A j tion, as will be understood by referenceto Fig. 1.4 A lock ring 30 is preferably, eni- 3b ployed between a flanged portion of the capV 28 .and the boss 13. The cage section 16 is provided with a `series of ports 31 connnunicating with the chamber 20 and with thel valve chamber 32, and it is also provided g5 with aseries of ports 33 which alsocommunicatewith the chamber 20 and with the valve. chamber 32. The valve chamber 1 contains a valve 34 preferably of the ball type, which controls a port 35, which registers with a port 36 'in the handle .sleeve 1l.V This port 36 communicates with a passage 37 formed by a reces in the outer periphery of the casing 2v a'tv 'rear end, so that live l motive fluidv may Apts's into thepiston cham- 95,1 ber 39. a The 'cage'setion 17 is provided with a port 40 controlled by the valve 34, y, and said port registers with a port 41 inthe cage section 16, and the port 41 registers latterfport communicating with a passage which extends longitudinally through the barrel and communicates b v means of a port 44 with the forward end of the piston chamber 39.A

Intermediate the ends of the piston cham@ ber'39 one or more exhaust'port-s 45 are provided, which extend through the .side wall of the casing2 and Vcommunicate with the atmosphere. l Y v 1'10 46 designates a reciprocatory piston which a comprises 'a cylindrical holt having at its forward end an extension 'or striker 47 'of reduced diameter adapted to passthrough the aperture 48. which forms a continuation "1%15 ofthe piston .chamber 39, and which is of less diameter than the diameter-of said pisf. tonchamber 39, thereby forming a shoulder 49, at the forward end ofthe piston chain-A ber. It will be seen that b v such 'consti-uc; 120 tion, the` piston is prevented from passing' through the forward end vof the casing 2r (r the handle 5 from the casing 2. hf 50 designates a working tool which for 125 purpose of illustration. I have shown as coniprising a'rivet set of a conventional type. although *itV Awill be understood thatit yis withinthe scope of my invention to employ any desired type of a working tool in 'ace 18'0 cordance with the` character of work which is to be performed. The workingtool 50 is provided ,with a shank 51 of uniform diameterv in the present instance and adapted to be received in the aperture 52, which opens through the forward end ofthe casing 2 and which communicates at its rear end with the aperture 48. The working tool 50 is recessed to 'receive a deflected portion of a split ring 53, the rear end of which interlocks with a.

recess 54 in the outer periphery of the casing 2.

In 'the voperation of this embodimentof `my invention, the proper lmanipulation of the manually actuated'main inlet valve 12 permits the motive fluid to pass through the passage 11 through the passages formed by the grooves 19 into the chamber 20, and assuming that the parts are in the position seen in Fig. 2, the live motive fluid will pass through the ports 31 into the valve chamber 32, and since the valve is pw in its forward position, the live mot-ive iiuid may pass through the port 35, the ports 36 and 37 and into'the piston chamber 39 in rear of the piston 46, ,and causes the piston to move from the position seen in Fig. 2 into that seen in Fig. 1, and to impact against l the inner end of the shank 51 of the working tool 59. As soon as the piston 46 in its forward stroke passes beyond the ports 45, the motive fluid in rear of the piston may exhaust through the ports directly into the atmosphere, thereby reducing'the pressure in rear of thevalve 34, whereupon 'theA valve changes from the position seen -in Fig. 2 to that seen in Fig. 1, .due to the action of thev live motive fluid against the forward portion of the valve. The -live motive. fluid now passes through the ports 33 into the valve chamber 32, and therefrom through the port 40 and through the ports 41 and 42 into the passage 43 and through the port y44 into the piston chamber 39 in front othe'shoulder 55 on the piston and acting on.

this pressurearea, causes the piston46 to move rearwardly and to be returnedto its initial position.

Duringthis rearward movement, as soon as the shoulder passes the port 45, the motive fluid may exhaust through such ports into the atmosphere, thereby reducing `the pressure at the forward end of -the valve, whereupon the valve instantly V repeatedl I; have provided pression of motive fluid at the forward and at the rear end of the piston chamber may.

be automatically controlled.

Referring first to Fig. 6, it will beseen that the piston chamber 39 communicates by means of a compression port 56. with a passage 57 which .extends rearwardly through the casing 2 and communicates.

with an exhaust port 58, which .is controlled by means of the stem 59 of a valve 60, the rear end of which isof a different diameter than the valve stem 59 `and reciprocates in *a chamber 61 which opens intothe rear end of the plst'on chamber 39 by means of a port 62. The passage 43 atits rear end com-A municates bymeans of a vport 63 with a pe! ripheral groove 64 of the casing'2. This groove 64 communicates by means of a port 65 with a valve chamber 66 in which is located a cylindricalvalve, 67, said valve controlling a port 68 which leads through the casing 2 and the handle 'sleeve 4 to the atp' mosphere.

69 designates a passage which communicates with the piston chamber '39' by means of the compression port 70, said port '70 b'eing located a desired distance from the vorward end of the piston chamber 39. The

passage 69 communicates with the passage 66 and is of a different diameter than said passage thereby formingva seat 71 for the valve. 67. The groove 64 communicates by means of a port 38 with the forward end Yof the valve chamber 61.

o In'this embodiment ofY my invention, seen 1n F1gs..6 .to 10 inclusive, the reciprocation of the' piston is effected in a' similar manner to that described with reference to Figs. 1 l and 2, except that I providek compression relief valves in order tovary the amount 'ofg compression 'at each the piston. a

`Assuming that the parts are in the posilive'motive fluid passes through the port 62 into the valve chamber 61 and owing to the greater pressure area at Ythe rear end ofthe valve 60, such valve 'will be retained during the forward stroke of the piston '46 in the position seen in Fig. 6 and after the end of the lstroke ofv tion seen in Fig. 6, the live motive Huid pisses into the piston chamber 39 in rear' ofzthe piston 46 to effect the forward move# lnient of the piston. At the same time, the

piston passes the port 56, the .live motive fluid cannot pass through said-portand the passage 57 tothe exhaust port 58 as the valve at this time closesuthls port.

This

port 58 is kept closed during practically the entirel forward movement of the piston ac cording to the time at which the'dlstribution valve changes its position. After the shoulder 55 of the piston 46 passes the ports 45 such ports are closed and the compression in advance ofthe piston is' rcduced,.

due to the air which is being compressed,

passingthrough the port. 7 0 passage 69, and 130 tliepport 68, it being understood that this compression causes the valve 67 to uncover said-port 68 `since the pressure has previously been relieved in rear of the valve 67.

Assuming now that 'the fluid distribution l valve 34vfis in the position seen in Fig. 8, the 1ive\motive iuid passes through' the passage 43,. and the port 44 in front of the'pis- The' live motive fluid at -,the.port 65 intov the valve chamber'. 66 in rear of the valve 67 and .owing to the live motive fluidi-pressure at the rear end of thevalve 67, the la'tter is maintained against its Seat 71 during therearward movement of v the piston46.

The cycle ofthe operation as above described i@then repeated.

- It will of course vbe understood that it is within the4 scope of my invention to locate the port 56 and the port 70 at any desireddistance from the ends of the piston chamber in order to vary the amount of compress'ion at the forward and rear strokes of the piston and in some cases one or both ofv the Icompression and relief valves and'their ports and passagespmay be dispensed with in ac- .cordance with thecharacter of work which Y is to be accomplished.

`ilocatedI It yis also to'be understood that while E show the compression and relief valves, for purposes* wallsjof" he casing, I do not desire to be, lim- 's location, since in many cases practice they will be preferably Y Y, he `4 handle sleeve or the head block at the end ofthe piston casing..l It is also within the scope of my invention to em-` ploy the principle herein involved in connection with pneumatic percussive .tools L of such as for example,l rock. drills any type ind pneumatic hammers and it Wlll 0f course be apparent that by the proper loca- Y v. tion'ofthe portsand passages, the hammer-` ing pistonl may. have a length of stroke greater' or lessthan its own 'length in. ac

cordance with the character of the work which is t'o be accomplished and the ,speed y andthe force ofthe hammering action of the piston will be correspondingly varied.4

When itisdesired to remove .thevalve cage forV the purpose of inspection or repair, itis simply necessary to remove the cap 28 v.and to insert an extracting device, such as for example, a standardy screw threaded bolt,` into the threaded 'lug 24, whereupon theen-` tire -valve 'cage lwith the valvecan here;

moved from the valve cage 'pocketjf-iii` Vof illustration, as located in the it is located. The locking and registering device 26 is then removed whereupon the valve cage sections 16 and. 17 may be readily taken a art and the valve removed if, desired. wing to the provision of the llocking and'registering device 26, the vports 35 and 41 in the valve cage will be accurately alined with lrespect to the ports k36 and-42,

respectively, in the sleeve or vhead block 4.

It will also be seen that owing to the man-` ner in ,which the fastening device' 9 inter'- 'j 1 locks with both the casing 2 and the sleeve tive rotation of the sleeve ,or head block and the casing is positively prevented, so that such parts are lockedv to prevent not only their relative rotation but .alsoso 'as to pre# vent their relative longitudinal movement.

The coacting faces of the sleeve or head .or head block 4, that the ports 36 and 42willv I' be brought into accurate register with corresponding ports in the casing and the relaffmv block and thecasing are preferably tapered, j

,but this is not necessaryin all cases arising jin practice and these faces may be made straight, if desired. .It is preferable to have such parts tapered for ease of rconnecting v or disconnecting such parts.

t In case the handlebecomes inserted through the'front end lofthe tool,

` so as to contact with the front endof the piston, so that the piston may be pushed Y ixedto the `casing'so that it is'not readilyqremovable,

the working toolma-y .be removed and a bar '9' rearwardly until its rear end 'abuts against"V a solid portion of the sleeve or head block and the requisite pressure can then be eX'- erted to remove the sleeve or head block from the casing without any injury whatever to the fluid distribution "valve or-its adjuncts or injury to the handle or the cas- 105 ioo g. .A It will also be seen thatvthe valve cage ymay be removedor inserted in position without necessitating the removal of the handle from thecasing and that thehandle may be removed from the casing without necessitat- "fingpthe removal of the valve mechanism. V

A pneumatic percussive tool constructed in Aaccordance with my present invention conforms to the laws of thoseStates which 115 render` itcompulsory to employ in conjunction with devices of this character means to prevent the ejection oflthe piston from the casing, since in my present construction'the pistoncanbe removed only from the rear end of the casing-.

Another important tion. is the arrangement of ports",y and passages so that if thev working tool has been removed the `piston will not reciprocate when the hammer is heldinY a=horizontal or downfeatureof my invenl ward direction and when held upwardly the piston will not advance far enough to strike the retaining wall or shoulder at the for" y ward end ofthe piston'chamber. This is a 1 30 particularly desirable feature as it prevents abuse of the tool by the piston battering the retaining Wall if the hammer is allowed to operate by stupid or careless workmen when the working tool is not in place.

Many pneumatic tools have heretofore been seriously injured by such practice.

For .the purpose of illustration the casing is shown as adapted to be manually held by the operator and the head block is therefore shown with a grasping handle provided with a manually ,controlled valve but it is to be understood that my invention is not limited to such construction since in many cases in practice the casing is notV provided with a grasping portion, as for example, in some types of rock drills, sand rammers, riveting hammers of large size, rivet busters, and` other devices. ,Y

I make no claim herein per se to the coacting tapered faces-of the head block and casing since such features are described and generically claimed in my copending appli'- cation Serial No. 83,470, tiled March 11th,

It will now be apparent thatI have* devised a novel and useful'construction of a pneumatic percussive tool which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and iyhile I have, in the present instance, shown and described preferred embodiments thereof which will give in practice satisfactory and reliablev re sults, it is to be understood that the same are susceptible of modification in various partic- .ulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

jHaving thus described my invention, what I claim asnevv anddesire to secure by Letters Patent, is

1. A percussive tool, comprisinga casing having a piston chamber With exhaust ports .intermediate the ends thereof, a head block having a split sleeve recessed to receive ythe rear end of said casing, inlet ports common 'to Said head block and the side wall of said the piston chamber, ahead block having a faces of. the casing A n Q l l smooth;and unobstructed but provided' with split sleeve recessed to receive. the rear end of the casing and having inlet ports to register with the ports inthe casing, theco-cting and head block being a connnolnv transversely extending-aperture,

va locking device in said aperture serving to maintain theregister of said-ports and to Qclampsaid sleeve tothe casing to form a 4fluid tight joint between its inlet ports, a piston-Tin the piston chamber, and means to alternately 4'admit motive fluid to, said inlet ports.

3. A permissive tool, comprising a casinghaving a piston" chamber, -a reciprocatory piston in said piston chamber, a head block receiving one end of the casing and provided with a valve cage pocket having akey-vvay,

valve mechanism in the cage pocket and having means to engage the key-Way, ports and l passages common to the head block'and casing yto control said piston and controlled by said valve, and means to lock the head block` and casing to prevent their relative rotation and their relative longitudinal movement.

4. A percussive tool, comprising a casing having a piston chamber, a reciprocatory piston in said'piston chamber, a head block receiving one end of the casing and provided With'a valve cage 4pocket having a key-Way, valve mechanism in the cage pocket and having means to engage the lrcyway, ports and passages common to the headA block and casing to control said piston and controlled by said valve, means to lock the head block and casing to prevent their relative rotation and their relative longitudinal movement, and lsaid valve mechanism having means to engage an extracting tool whereby the valve mechanism may be removed as a unit of structure from said valve cage'pocket.

5. In a percussive tool, a head block having a valve cage pocket and means to pass motive fluid thereto, a ported valve cage to it said pocket and consisting of sections forming a valve chamber, a locking and alining member serving to secure the cage sections together and interlocking with the wall of the valve cage pocket to aline the valve cage, and a valve to control the ports in the valve cage.-

6. `In a percussive tool, a head block hav' ing a valve cage pocket and means to pass motive fluid thereto, a ported valve cage to 'iit said pocket and consisting of sections forming a vvalve chamber, a locking and alining member .serving to secure the cage sections together and interlocking with the Wall of the valve cage pocket to aline the `valve cage', and a ball'valve to control the ports in the valve cage` j 7. In a percussive tool, a head block having a valve cage pocket and means tov pass motive fluid thereto, a portedvalve cage to fit said pocket and consisting of sections forming a valve chamber, a 'locking and.-

aliningmember serving to secure the cage sections. together and interlocking with the wall of 4thevalve cage pocket to aline the valve cage, means to close the open end. of

iso t i said pocket, and. a valve to control the ports i' a valve cage po sections together and interlocking with the in the valvecage.

8. Ina ,percussive tool, ahead block hav- -cket and means to'pass' motive fluid thereto, a4 ported valve cage to fit .said pocket and consisting of sections forming a valve chamber, a locking and' alining 'member serving to secure the cage wall of the valve. c'age vpocket to' aline the valve cage, 'a cap secured to the head block and covering thepo'cket, a spring between the cap and the v trol the ports in valve cage, and a'valve .to conthe valve cage.4

9. Ina percussive tool, a head ing a valve cage pocket and means to pass motive iuid thereto, a ported valve cage to telescopic fit said pocket and consisting of.

' a locking sections forming' a valve chamber, and alini'ng member. serving valve cage, and a valveto control the ports in the valve cage. 4 I

f 10. A percussive tool, comprising a casing having a piston chamber with exhaust ports intermediate its ends, a passage leading from the rear-portion of the casing to communicate with the vforward end of the piston chamber and with a peripheral groove in communication with said passage, a compression exhaust portcommunicating 'withthepiston chambernear therear end1 thereof, a valve chamberhaving a port'communica'ting with said groove and having 'a' port communicating with the rear end of said piston chamber, said valve controlling saidcompression exhaust port.

11. A percussive tool, comprising a casing' having a piston chamber with exhaust ports,

a piston inthe piston chamber, means to iiiy troduce live motive iiuid to opposite ends of return pression 'Xhaust the piston chamber, compression `at one end of the piston chamber and including a valve actuated in both directions by live motivev Huid, and devices.

-to reduce the compression at the outward end of the piston chamber and including a valve actuated tive fluid and in compression of motive the reverse direction by fluid between the piston and the end of the piston chamber. A

12. A percussi've tool, comprising a casing having a -pistonchamber with main exhaust ports, a -piston orsaid piston chamber, aV

compression exhaust port communicating with the piston chamber near its rear end, a valve controlling said port, means to close l l exhaust of motive fluid, a

rocable in the casing, valve mechanismy con- -125 said valve during the-forward stroke of the piston, means to open 'said valve'duringthe stroke of the piston, ar secondY comport opening into the pis-- .ton chamberliflear .imma means block havi to secure the' cage sections together and interlocki g with thewall of the valve cage pocket to a ine the Y VI'rigidly lock4 the sections' vsaid cage.

ber and provided with communicating by ports with said valve chamber, a valve in said valve chamber, and

the cage sections together whereby they may be insertedI in andV re'- 105 means to reduce thev in one direction by live mo,-

y its forward end, a second` Avalve controlling the second 'compression exto move said second valve and alining member to secure 'thegsections together. i t Y 14. The combination of a .casing having .30

ports and passages for the' admission and exhaust 'of motive fluid,` a piston reciproca# ble in the 'casing, valve mechanism controlling said admission ports and passages, comprisinga cage formed in two separable sec- V tions, each of which forms a valve seat,.one of said sections forming a valve'chaniber, a valve in said valve chamber, means to admit motlv'e fluid to the valve chamber, and means to means serving also as an alining device for 15. The combination of a casing having .ports and passages for the admission and exhaust of .motive fluid, a piston reciproca- 95V ble in the '.casing, valve -mechanism 'con'- troliing saidadmission ports and passages, comprising a cage formed in two separable sections, each of which forms a valve seat, one of said .sections forming a an ann ar` 'groove means to lock movedl from place as a unit fstmcture:

' 16- 'The Combination of c a asin.:A having 'orts and passages for the admission andv exhaust of motive fluid, a pistonvffreci'p-'f l rocable in .the trolling said admission ports and passages, comprising a cage formed in two separable sections, each of which vforms a valve seat, aport'in each cage section communicating with; a casing admission poiiafav valve con- 115 trolling said'ports and-seats, a locking dei vice' for the cage sections, .and one of said" 4 sections having a lug adapted to be -en, ",a'ge`d l by anextracting device whereby theivalve mechanism may 17; The combination .ofY acasing ports and passages for each other andhavingports to registervwith 1301 i together, said 'l 90 alvey cham- 160- casnig, valve mechanism con-A `1110` bev inserted into and' re- V1 2()v moved from placeas a unit. 1 o

the Aadmission andV piston recip-` the casing admissionv ports, one ofthe sections forming a valve chamber, a valve in the valve chamber, and a locking and alining device for said sections to secure them together and to bring certain of their ports into alinement with the casing admission ports.

18. The vcombination of a casing having ports and passages for the admission and exhaust of motive fluid, a piston reciprocable in the casing, valve mechanism controlling said admission ports and passages, comprising a cage formed intwo separable sections, each of which forms a valve seat, one of the cage sectionsJ having an annular groove and a longitudinal groove in its periphery leading from saidv groove' and open at oneend, such cage section forming a valve chamber, and a valve in the'valve 19. The combination of a casing having ports and passages for the admission and exhaust of motive Huid, a piston reciprocable init-he casing, valve mechanism controlling said admission ports and passages, comprising a cage formed in two separable sections, eachof which forms a valve seat,

chamber and the other'cage section forming a closure for the valve chamber, one ci said sections having a threaded lug adapted to -valve cage and said cap. one of the cage sections Jforming a valve receivea standard screw threaded bolt, and

a valve in the valve chamber.

20. The combination of a casing having ports and passages for the admission and exhaust of motive fluid, a piston recip\ rocable in the casing, valve mechanism controlling` said admission ports and passages, comprising a cage formed in two separable sections, each of which forms' a valve seat, a -valve to control said seats, a locking and alining member to secure the sections together, said casing having a valve cage pocket, and a spring to retain the valve cage in the valve cage pocket.

2l. The combination of a casing' having ports and passages for the admission and exhaust of motive fluid, a piston. reciprocable in the casing, valve mechanism controlling said admission ports and passages, comprising a cage formed 1n two separable vpocket to receive thej'alvel cage, a cap closing said pocket, and a spring between said oHARLEs H. HaEsELER. VWitnesses:

H. S. FAIRBANKS, C. D. McVAY. 

